Patent · US Expired

Level shifting circuit having a fixed output common mode level

US6191635A · kind A · utility

4Cited by
11References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 31, 1999
Grant dateFeb 20, 2001
Priority date
Expiry dateAug 31, 2019

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03K19/01831
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

The invention relates to an electronic circuit, and in particular embodiments to a level shifting circuit having an output common mode voltage independent of the input common mode voltage, and unity differential signal gain. The circuit receives first and second input voltages, referenced to a first voltage supply rail, and has first and second resistors, each connected to the first input terminal, and third and fourth resistors, each connected to the second input terminal, the second and third resistors having equal resistance values. The first resistor is also connected to a first output terminal, the fourth resistor is also connected to a second output terminal, and the second and third resistors are also connected together at a reference node. A first current source draws a current through the first resistor, a second current source draws a current through the fourth resistor, and a third current source draws a current through the second and third resistors and the reference node, and sets a reference voltage, referenced to the second voltage supply rail, at the reference node. The first and fourth resistors, and the first and third current sources, are such that the voltage dr…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.